Multipotent cells from the human third molar: feasibility of cell-based therapy for liver disease

Abstract Adult stem cells have been reported to exist in various tissues. The isolation of high-quality human stem cells that can be used for regeneration of fatal deseases from accessible resources is an important advance in stem cell research. In the present study, we identified a novel stem cell, which we named tooth germ progenitor cells (TGPCs), from discarded third molar, commonly called as wisdom teeth. We demonstrated the characterization and distinctiveness of the TGPCs, and found that TGPCs showed high proliferation activity and capability to differentiate in vitro into cells of three germ layers including osteoblasts, neural cells, and hepatocytes. TGPCs were examined by the transplantation into a carbon tetrachloride (CCl₄)-treated liver injured rat to determine whether this novel cell source might be useful for cell-based therapy to treat liver diseases. The successful engraftment of the TGPCs was demonstrated by PKH26 fluorescence in the recipient's rat as to liver at 4 weeks after transplantation. The TGPCs prevented the progression of liver fibrosis in the liver of CCl₄-treated rats and contributed to the restoration of liver function, as assessed by the measurement of hepatic serum markers aspartate aminotransferase and alanine aminotransferase. Furthermore, the liver functions, observed by the levels of serum bilirubin and albumin, appeared to be improved following transplantation of TGPCs. These findings suggest that multipotent TGPCs are one of the candidates for cell-based therapy to treat liver diseases and offer unprecedented opportunities for developing therapies in treating tissue repair and regeneration.     

A Novel Isourazole Herbicide, Fluthiacet-Methyl, is a Potent Inhibitor of Protoporphyrinogen Oxidase after Isomerization by Glutathione S-Transferase

A novel isourazole herbicide, fluthiacet-methyl (methyl [[2-chloro-4-fluoro-5-[(5,6,7,8-tetrahydro-3-oxo-lH,3H-[l,3,4]thiadiazolo[3,4-a]pyridazin-l-ylidene)amino]phenyrjthio]acetate;experimental code name, KIH-9201) promoted the leakage of electrolytesfrom cotyledons of velvetleaf (Abtilon theophtasti Medic) andcotton (Gossypium hirsutum L.) plants that are sensitive tothis compound. It induced the accumulation of protoporphyrinIX in cotyledons of cotton and inhibited Chl biosynthesis incotyledons of velvetleaf and cotton at low concentrations (I₅₀values, 10–12 nM). Fluthiacet-methyl was converted toits urazole by glutathione S-transferase that had been partiallypurified from velvetleaf. The urazole inhibited protoporphyrinogenoxidase (Protox, EC 1.3.3.4 [EC] ) from some plants, including velvetleaf,at low concentrations (I₅₀ values, 5.1–11 nM), whereasfluthiacet-methyl was not as potent. The effects in vivo (electrolyteleakage and inhibition of Chi biosynthesis) of fluthiacet-methylwere correlated with the inhibition of Protox activity by theurazole and not with the action of fluthiacet-methyl itself.From these results, it is concluded that fluthiacet-methyl inhibitsProtox activity after conversion to the corresponding urazoleby glutathione S-transferase. It is in this way that fluthiacet-methylexerts its effect as a light-dependent peroxidizing herbicide. (Received November 1, 1994; Accepted March 6, 1995)     

Detection of Escherichia coli O157:H7 in the Beef Marketed in Malaysia

Twelve strains of Escherichia coli O157:H7 were isolated from 9 of 25 beef samples purchased from retail stores in Malaysia. These strains produced Shiga toxin 2 with or without Shiga toxin 1 and had the eae gene and a 60-MDa plasmid. The antibiograms and the profiles of the arbitrarily primed PCR of the strains were diverse, suggesting that the strains may have originated from diverse sources.     

Gastrointestinal specific anxiety in irritable bowel syndrome: validation of the Japanese version of the visceral sensitivity index for university students

Objective

The visceral sensitivity index (VSI) is a useful self-report measure of the gastrointestinal symptom-specific anxiety (GSA) of patients with irritable bowel syndrome (IBS). Previous research has shown that worsening GSA in IBS patients is related to the severity of GI symptoms, suggesting that GSA is an important endpoint for intervention. However, there is currently no Japanese version of the VSI. We therefore translated the VSI into Japanese (VSI-J) and verified its reliability and validity.

Material and methods

Participants were 349 university students aged 18 and 19 years and recruited from an academic class. We analyzed data from the VSI-J, Anxiety Sensitivity Index (ASI), Hospital Anxiety and Depression scale (HAD), and Irritable Bowel Syndrome Severity Index (IBS-SI). The internal consistency, stability, and factor structure of the VSI-J and its associations with anxiety, depression and severity measures were investigated.

Results

The factor structure of the VSI-J is unidimensional and similar to that of the original VSI (Cronbach’s α?=?0.93). Construct validity was demonstrated by significant correlations with ASI (r?=?0.43, p?<?0.0001), HAD-ANX (r?=?0.19, p?=?0.0003), and IBS-SI scores (r?=?0.45, p?<?0.0001). Furthermore, the VSI-J was a significant predictor of severity scores on the IBS-SI and demonstrated good discriminant (p?<?0.0001) and incremental (p?<?0.0001) validity.

Conclusion

These findings suggest that the VSI-J is a reliable and valid measure of visceral sensitivity.

     

Ultrasound enhances retrovirus-mediated gene transfer

Viral vector systems are efficient for transfection of foreign genes into many tissues. Especially, retrovirus based vectors integrate the transgene into the genome of the target cells, which can sustain long term expression. However, it has been demonstrated that the transduction efficiency using retrovirus is relatively lower than those of other viruses. Ultrasound was recently reported to increase gene expression using plasmid DNA, with or without, a delivery vehicle. However, there are no reports, which show an ultrasound effect to retrovirus-mediated gene transfer efficiency. Retrovirus-mediated gene transfer systems were used for transfection of 293T cells, bovine aortic endothelial cells (BAECs), rat aortic smooth muscle cells (RASMCs), and rat skeletal muscle myoblasts (L6 cells) with beta-galactosidase (beta-Gal) genes. Transduction efficiency and cell viability assay were performed on 293T cells that were exposed to varying durations (5 to 30 seconds) and power levels (1.0 watts/cm(2) to 4.0 watts/cm(2)) of ultrasound after being transduced by a retrovirus. Effects of ultrasound to the retrovirus itself was evaluated by transduction efficiency of 293T cells. After exposure to varying power levels of ultrasound to a retrovirus for 5 seconds, 293T cells were transduced by a retrovirus, and transduction efficiency was evaluated. Below 1.0 watts/cm(2) and 5 seconds exposure, ultrasound showed increased transduction efficiency and no cytotoxicity to 293T cells transduced by a retrovirus. Also, ultrasound showed no toxicity to the virus itself at the same condition. Exposure of 5 seconds at the power of 1.0 watts/cm(2) of an ultrasound resulted in significant increases in retrovirus-mediated gene expression in all four cell types tested in this experiment. Transduction efficiencies by ultrasound were enhanced 6.6-fold, 4.8-fold, 2.3-fold, and 3.2-fold in 293T cells, BAECs, RASMCs, and L6 cells, respectively. Furthermore, beta-Gal activities were also increased by the retrovirus with ultrasound exposure in these cells. Adjunctive ultrasound exposure was associated with enhanced retrovirus-mediated transgene expression in vitro. Ultrasound associated local gene therapy has potential for not only plasmid-DNA-, but also retrovirus-mediated gene transfer.     

Components of essential oils extracted from leaves and shoots of abies species in Japan

The essential oils extracted from the leaves and the shoots of five Abies species (Pinaceae) growing in Japan, i.e., A. firma, A. homolepis, A. veitchii, A. mariesii, and A. sachalinensis, were characterized by GC-FID and GC/MS analyses. The yields of the essential oils extracted from A. sachalinensis were the highest among them. A significant amount of α-pinene was contained in the essential oils of all the Abies species examined. In A. homolepis and A. veitchii, significant differences in the content of the essential oils were found depending on whether these were extracted from the leaves or from the shoots. Regarding the enantiomeric ratio of α-pinene, the (+)-enantiomer was predominant in the oil extracted from the leaves of A. firma, while (-)-α-pinene was present in higher amounts in the oils of A. veitchii (leaves and shoots), A. mariesii (leaves and shoots), and A. sachalinensis (shoots). The fact that there may be a quantitative and qualitative difference in the components of the essential oils extracted from the different parts of a plant was investigated by cluster analysis.